With the development of modern technology, there are many electric devices installed with a lens for a user to easily take photography. However, some electric devices, such as a mobile phone, a table PC, and a notebook, are not allowed to exchange the lenses. As a result, it usually happened that a desired picture cannot be obtained in a specific situation that the lens capability of the electric devices is limited. For example, in a prior art, a focal length of the lens of a conventional mobile phone is unchangeable, so it becomes difficult for taking the lens of the mobile phone as a suitable camera device to take a far picture well. Accordingly, an idea of providing an additional detachable lens for the electric device is submitted in an attempt to enable these conventional electric devices to be suitable for any picture taking situation.
However, since a conventional detachable lens is only for some specific electric devices, the detachable lens compatible to a specific electric device cannot be used for a different device, and therefore a user needs to buy several different kinds of detachable lenses for different electric devices to thus cost money and decrease the applicability for the electric device having lens and the detachable lens.